Navigation Links
New statistical model moves human evolution back 3 million years
Date:11/5/2010

Evolutionary divergence of humans from chimpanzees likely occurred some 8 million years ago rather than the 5 million year estimate widely accepted by scientists, a new statistical model suggests.

The revised estimate of when the human species parted ways from its closest primate relatives should enable scientists to better interpret the history of human evolution, said Robert D. Martin, curator of biological anthropology at the Field Museum, and a co-author of the new study appearing in the journal Systematic Biology. Here is a link to the article: http://sysbio.oxfordjournals.org/content/early/2010/11/04/sysbio.syq054.full.html?ijkey=CaQif1LgTAd7xOD&keytype=ref

Working with mathematicians, anthropologists and molecular biologists, Martin has long sought to integrate evolutionary information derived from genetic material in various species with the fossil record to get a more complete picture.

Comparing DNA among related animals can provide a clear picture of how their shared genes evolved over time, giving rise to new and separate species, Martin said. But such molecular information doesn't yield a timetable showing when the genetic divergence occurred.

Fossil evidence is the only direct source of information about long-extinct species and their evolution, Martin and his colleagues said, but large gaps in the fossil record can make such information difficult to interpret. For a generation, paleontologists have estimated human origins at 5 million to 6 million years ago.

But that estimate rests on a thin fossil record. By looking at all of today's primate species, all of the known fossil primates and using DNA evidence, computer models suggest a longer evolutionary timetable. The new analysis described in the Systematic Biology paper takes into account gaps in the fossil record and fills in those gaps statistically.

Such modeling techniques, which are widely used in science and commerce, take into account more overall information than earlier processes used to estimate evolutionary history using just a few individual fossil dates, Martin said. It can give scientists a broader perspective for interpreting data.

One example is a skull fossil discovered in Chad (central Africa) earlier in this decade. The fossil, named Sahelanthropus tchadensis and nicknamed Touma (which means "hope of life" in the local Goran language), raised great interest because it has many human characteristics. But consensus on how to classify the discovery has been elusive particularly because the fossil is about 7 million years old, well beyond the accepted time frame for human evolution.

Under the new estimate, Touma would fall within the period after the human lineage split from chimpanzees, Martin said.

The new approach to dating evolutionary history builds on earlier work by Martin and colleagues. In 2002, they published a paper in Nature that argues the last common ancestor of today's primates lived some 85 million years ago.

This implies that for 20 million years before dinosaurs became extinct, early versions of primates also lived and evolved. It challenged the accepted theory that primates and other mammals didn't really thrive on the planet until dinosaurs were gone.

After that paper was published, Martin said he expected someone would apply the new statistical techniques to the question of human evolution, but when no one did, "We decided to do it ourselves."


'/>"/>

Contact: Nancy O'shea
noshea@fieldmuseum.org
312-371-7117
Field Museum
Source:Eurekalert

Related biology news :

1. Hobbits are a new human species -- according to the statistical analysis of fossils
2. Carnegie Mellon researchers apply new statistical test
3. Supercomputer makes it possible to develop a Brazilian Global Climate System Model
4. Tutorial addresses stochastic modeling in biological process
5. NYU Courant researchers develop algebraic model to monitor cellular change
6. Study improves accuracy of models for predicting ozone levels in urban areas
7. Imperial and NTUs new medical school aspires to be global health care role model
8. Mathematical model may result in better environment measures for the Baltic
9. Modeling study identifies characteristics of high elk-use areas in western Oregon, Washington
10. Computational model of swimming fish could inspire design of robots or medical prosthetics
11. Model unfolds proteins gently
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... 2016 On Monday, the Department of Homeland ... share solutions for the Biometric Exit Program. The Request ... Protection (CBP), explains that CBP intends to add biometrics ... the United States , in order to deter ... Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/9/2016)... 2016  Perkotek an innovation leader in attendance control systems is proud to announce ... for employers to make sure the right employees are actually signing in, and to ... ... ... ...
(Date:6/2/2016)... NEW YORK , June 2, 2016   The ... (Weather), is announcing Watson Ads, an industry-first capability in which ... advertising, by being able to ask questions via voice or ... Marketers have long ... with the consumer, that can be personal, relevant and valuable; ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... 2016 Andrew D ... http://doi.org/10.17925/OHR.2016.12.01.22 Published recently in ... from touchONCOLOGY, Andrew D Zelenetz , discusses ... care is placing an increasing burden on healthcare ... therapies. With the patents on many biologics expiring, ...
(Date:6/23/2016)... ... June 23, 2016 , ... ClinCapture, the only ... Center and will showcase its product’s latest features from June 26 to June ... scientific poster on Disrupting Clinical Trials in The Cloud during the conference. ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, ... tools designed, tuned and optimized exclusively for Okuma CNC machining centers at The ... of a collaboration among several companies with expertise in toolholding, cutting tools, machining ...
(Date:6/23/2016)... ReportsnReports.com adds 2016 global ... pharmaceuticals section with historic and forecast data along ... Complete report on the Cell Culture ... companies and supported with 261 tables and figures ... The Global Cell Culture Media Industry ...
Breaking Biology Technology: